Day 8 Complete

day08/input

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+rect 1x1
+rotate row y=0 by 5
+rect 1x1
+rotate row y=0 by 5
+rect 1x1
+rotate row y=0 by 5
+rect 1x1
+rotate row y=0 by 5
+rect 1x1
+rotate row y=0 by 2
+rect 1x1
+rotate row y=0 by 2
+rect 1x1
+rotate row y=0 by 3
+rect 1x1
+rotate row y=0 by 3
+rect 2x1
+rotate row y=0 by 2
+rect 1x1
+rotate row y=0 by 3
+rect 2x1
+rotate row y=0 by 2
+rect 1x1
+rotate row y=0 by 3
+rect 2x1
+rotate row y=0 by 5
+rect 4x1
+rotate row y=0 by 5
+rotate column x=0 by 1
+rect 4x1
+rotate row y=0 by 10
+rotate column x=5 by 2
+rotate column x=0 by 1
+rect 9x1
+rotate row y=2 by 5
+rotate row y=0 by 5
+rotate column x=0 by 1
+rect 4x1
+rotate row y=2 by 5
+rotate row y=0 by 5
+rotate column x=0 by 1
+rect 4x1
+rotate column x=40 by 1
+rotate column x=27 by 1
+rotate column x=22 by 1
+rotate column x=17 by 1
+rotate column x=12 by 1
+rotate column x=7 by 1
+rotate column x=2 by 1
+rotate row y=2 by 5
+rotate row y=1 by 3
+rotate row y=0 by 5
+rect 1x3
+rotate row y=2 by 10
+rotate row y=1 by 7
+rotate row y=0 by 2
+rotate column x=3 by 2
+rotate column x=2 by 1
+rotate column x=0 by 1
+rect 4x1
+rotate row y=2 by 5
+rotate row y=1 by 3
+rotate row y=0 by 3
+rect 1x3
+rotate column x=45 by 1
+rotate row y=2 by 7
+rotate row y=1 by 10
+rotate row y=0 by 2
+rotate column x=3 by 1
+rotate column x=2 by 2
+rotate column x=0 by 1
+rect 4x1
+rotate row y=2 by 13
+rotate row y=0 by 5
+rotate column x=3 by 1
+rotate column x=0 by 1
+rect 4x1
+rotate row y=3 by 10
+rotate row y=2 by 10
+rotate row y=0 by 5
+rotate column x=3 by 1
+rotate column x=2 by 1
+rotate column x=0 by 1
+rect 4x1
+rotate row y=3 by 8
+rotate row y=0 by 5
+rotate column x=3 by 1
+rotate column x=2 by 1
+rotate column x=0 by 1
+rect 4x1
+rotate row y=3 by 17
+rotate row y=2 by 20
+rotate row y=0 by 15
+rotate column x=13 by 1
+rotate column x=12 by 3
+rotate column x=10 by 1
+rotate column x=8 by 1
+rotate column x=7 by 2
+rotate column x=6 by 1
+rotate column x=5 by 1
+rotate column x=3 by 1
+rotate column x=2 by 2
+rotate column x=0 by 1
+rect 14x1
+rotate row y=1 by 47
+rotate column x=9 by 1
+rotate column x=4 by 1
+rotate row y=3 by 3
+rotate row y=2 by 10
+rotate row y=1 by 8
+rotate row y=0 by 5
+rotate column x=2 by 2
+rotate column x=0 by 2
+rect 3x2
+rotate row y=3 by 12
+rotate row y=2 by 10
+rotate row y=0 by 10
+rotate column x=8 by 1
+rotate column x=7 by 3
+rotate column x=5 by 1
+rotate column x=3 by 1
+rotate column x=2 by 1
+rotate column x=1 by 1
+rotate column x=0 by 1
+rect 9x1
+rotate row y=0 by 20
+rotate column x=46 by 1
+rotate row y=4 by 17
+rotate row y=3 by 10
+rotate row y=2 by 10
+rotate row y=1 by 5
+rotate column x=8 by 1
+rotate column x=7 by 1
+rotate column x=6 by 1
+rotate column x=5 by 1
+rotate column x=3 by 1
+rotate column x=2 by 2
+rotate column x=1 by 1
+rotate column x=0 by 1
+rect 9x1
+rotate column x=32 by 4
+rotate row y=4 by 33
+rotate row y=3 by 5
+rotate row y=2 by 15
+rotate row y=0 by 15
+rotate column x=13 by 1
+rotate column x=12 by 3
+rotate column x=10 by 1
+rotate column x=8 by 1
+rotate column x=7 by 2
+rotate column x=6 by 1
+rotate column x=5 by 1
+rotate column x=3 by 1
+rotate column x=2 by 1
+rotate column x=1 by 1
+rotate column x=0 by 1
+rect 14x1
+rotate column x=39 by 3
+rotate column x=35 by 4
+rotate column x=20 by 4
+rotate column x=19 by 3
+rotate column x=10 by 4
+rotate column x=9 by 3
+rotate column x=8 by 3
+rotate column x=5 by 4
+rotate column x=4 by 3
+rotate row y=5 by 5
+rotate row y=4 by 5
+rotate row y=3 by 33
+rotate row y=1 by 30
+rotate column x=48 by 1
+rotate column x=47 by 5
+rotate column x=46 by 5
+rotate column x=45 by 1
+rotate column x=43 by 1
+rotate column x=38 by 3
+rotate column x=37 by 3
+rotate column x=36 by 5
+rotate column x=35 by 1
+rotate column x=33 by 1
+rotate column x=32 by 5
+rotate column x=31 by 5
+rotate column x=30 by 1
+rotate column x=23 by 4
+rotate column x=22 by 3
+rotate column x=21 by 3
+rotate column x=20 by 1
+rotate column x=12 by 2
+rotate column x=11 by 2
+rotate column x=3 by 5
+rotate column x=2 by 5
+rotate column x=1 by 3
+rotate column x=0 by 4

day08/main.go

@@ -0,0 +1,210 @@
+package main
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// First guess: 95 (too low)
+
+func main() {
+	if len(os.Args) < 3 {
+		fmt.Println("Expected Display Width & Height as Arguments")
+	}
+	input := stdinToStringSlice()
+	// Test Display:
+	// d := CreateDisplay(7, 3)
+	// Prod Display:
+	// d := CreateDisplay(50, 6)
+	width := atoi(os.Args[1])
+	height := atoi(os.Args[2])
+	d := CreateDisplay(width, height)
+	for idx, ins := range input {
+		fmt.Println(idx, ins)
+		d.ClearScreen()
+		d.ProcInstruction(ins)
+		d.PrintScreen()
+		time.Sleep(time.Millisecond * 75)
+	}
+	fmt.Println("Voltage Used: ", d.GetVoltage())
+}
+
+type Display struct {
+	Width  int
+	Height int
+	Screen [][]bool
+}
+
+func CreateDisplay(w, h int) *Display {
+	d := Display{Width: w, Height: h}
+	for i := 0; i < h; i++ {
+		var row []bool
+		for j := 0; j < w; j++ {
+			row = append(row, false)
+		}
+		d.Screen = append(d.Screen, row)
+	}
+	return &d
+}
+
+func (d *Display) ClearScreen() {
+	fmt.Print("\033[H\033[2J")
+}
+
+func (d *Display) PrintScreen() {
+	fmt.Print("\u250C")
+	for i := 0; i < d.Width; i++ {
+		fmt.Print("\u2500")
+	}
+	fmt.Println("\u2510")
+	for y := range d.Screen {
+		fmt.Print("\u2502")
+		for x := range d.Screen[y] {
+			if d.Screen[y][x] {
+				fmt.Print("\u2588")
+			} else {
+				fmt.Print(" ")
+			}
+		}
+		fmt.Println("\u2502")
+	}
+	fmt.Print("\u2514")
+	for i := 0; i < d.Width; i++ {
+		fmt.Print("\u2500")
+	}
+	fmt.Println("\u2518")
+}
+
+func (d *Display) SetWidth(w int) {
+	d.Width = w
+}
+
+func (d *Display) SetHeight(h int) {
+	d.Height = h
+}
+
+func (d *Display) ProcInstruction(ins string) {
+	pts := strings.Fields(ins)
+	switch pts[0] {
+	case "rect":
+		if len(pts) < 2 {
+			return
+		}
+		dim := strings.Split(pts[1], "x")
+		bldX := atoi(dim[0])
+		bldY := atoi(dim[1])
+		d.CreateRect(bldX, bldY)
+	case "rotate":
+		if len(pts) < 5 {
+			return
+		}
+		args := strings.Split(pts[2], "=")
+		switch pts[1] {
+		case "row":
+			if args[0] != "y" {
+				return
+			}
+			d.RotateRow(atoi(args[1]), atoi(pts[4]))
+		case "column":
+			if args[0] != "x" {
+				return
+			}
+			d.RotateCol(atoi(args[1]), atoi(pts[4]))
+		}
+	}
+}
+
+func (d *Display) CreateRect(x, y int) {
+	if y >= d.Height && x >= d.Width {
+		fmt.Println("  Error creating rect", x, y)
+		return
+	}
+	for i := 0; i < y; i++ {
+		for j := 0; j < x; j++ {
+			d.Screen[i][j] = true
+		}
+	}
+}
+
+func (d *Display) RotateRow(y, dist int) {
+	orig, err := d.GetRow(y)
+	if err != nil {
+		fmt.Println(err.Error())
+		os.Exit(1)
+		return
+	}
+	for i := range orig {
+		d.Screen[y][(i+dist)%d.Width] = orig[i]
+	}
+}
+
+func (d *Display) RotateCol(x, dist int) {
+	orig, err := d.GetCol(x)
+	if err != nil {
+		fmt.Println(err.Error())
+		os.Exit(1)
+		return
+	}
+
+	for i := range orig {
+		d.Screen[(i+dist)%d.Height][x] = orig[i]
+	}
+}
+
+func (d *Display) GetRow(y int) ([]bool, error) {
+	var ret []bool
+	if d.Height <= y {
+		return ret, errors.New("Invalid Row Requested")
+	}
+	for i := 0; i < d.Width; i++ {
+		ret = append(ret, d.Screen[y][i])
+	}
+	return ret, nil
+}
+
+func (d *Display) GetCol(x int) ([]bool, error) {
+	var ret []bool
+	if d.Width <= x {
+		return ret, errors.New("Invalid Column Requested")
+	}
+	for i := 0; i < d.Height; i++ {
+		ret = append(ret, d.Screen[i][x])
+	}
+	return ret, nil
+}
+
+func (d *Display) GetVoltage() int {
+	var ret int
+	for i := range d.Screen {
+		for j := range d.Screen[i] {
+			if d.Screen[i][j] {
+				ret++
+			}
+		}
+	}
+	return ret
+}
+
+func stdinToStringSlice() []string {
+	var input []string
+	scanner := bufio.NewScanner(os.Stdin)
+	for scanner.Scan() {
+		input = append(input, scanner.Text())
+	}
+	return input
+}
+
+func atoi(i string) int {
+	var ret int
+	var err error
+	if ret, err = strconv.Atoi(i); err != nil {
+		log.Fatal("Invalid Atoi")
+	}
+	return ret
+}

day08/problem

@@ -0,0 +1,89 @@
+Advent of Code
+
+--- Day 8: Two-Factor Authentication ---
+
+   You come across a door implementing what you can only assume is an implementation of two-factor authentication
+   after a long game of requirements telephone.
+
+   To get past the door, you first swipe a keycard (no problem; there was one on a nearby desk). Then, it displays a
+   code on a little screen, and you type that code on a keypad. Then, presumably, the door unlocks.
+
+   Unfortunately, the screen has been smashed. After a few minutes, you've taken everything apart and figured out how
+   it works. Now you just have to work out what the screen would have displayed.
+
+   The magnetic strip on the card you swiped encodes a series of instructions for the screen; these instructions are
+   your puzzle input. The screen is 50 pixels wide and 6 pixels tall, all of which start off, and is capable of three
+   somewhat peculiar operations:
+
+     • rect AxB turns on all of the pixels in a rectangle at the top-left of the screen which is A wide and B tall.
+     • rotate row y=A by B shifts all of the pixels in row A (0 is the top row) right by B pixels. Pixels that would
+       fall off the right end appear at the left end of the row.
+     • rotate column x=A by B shifts all of the pixels in column A (0 is the left column) down by B pixels. Pixels
+       that would fall off the bottom appear at the top of the column.
+
+   For example, here is a simple sequence on a smaller screen:
+
+     • rect 3x2 creates a small rectangle in the top-left corner:
+
+ ###....
+ ###....
+ .......
+
+     • rotate column x=1 by 1 rotates the second column down by one pixel:
+
+ #.#....
+ ###....
+ .#.....
+
+     • rotate row y=0 by 4 rotates the top row right by four pixels:
+
+ ....#.#
+ ###....
+ .#.....
+
+     • rotate column x=1 by 1 again rotates the second column down by one pixel, causing the bottom pixel to wrap back
+       to the top:
+
+ .#..#.#
+ #.#....
+ .#.....
+
+   As you can see, this display technology is extremely powerful, and will soon dominate the
+   tiny-code-displaying-screen market. That's what the advertisement on the back of the display tries to convince you,
+   anyway.
+
+   There seems to be an intermediate check of the voltage used by the display: after you swipe your card, if the
+   screen did work, how many pixels should be lit?
+
+   Your puzzle answer was _____.
+
+--- Part Two ---
+
+   You notice that the screen is only capable of displaying capital letters; in the font it uses, each letter is 5
+   pixels wide and 6 tall.
+
+   After you swipe your card, what code is the screen trying to display?
+
+   Your puzzle answer was _____________.
+
+References
+
+   Visible links
+   . http://adventofcode.com/
+   . http://adventofcode.com/2016/about
+   . http://adventofcode.com/2016/support
+   . http://adventofcode.com/2016/events
+   . http://adventofcode.com/2016/settings
+   . http://adventofcode.com/2016/auth/logout
+   . http://adventofcode.com/2016
+   . http://adventofcode.com/2016
+   . http://adventofcode.com/2016/leaderboard
+   . http://adventofcode.com/2016/stats
+   . http://adventofcode.com/2016/sponsors
+   . http://adventofcode.com/2016/sponsors
+   . https://en.wikipedia.org/wiki/Multi-factor_authentication
+   . https://en.wikipedia.org/wiki/Requirement
+   . https://en.wikipedia.org/wiki/Chinese_whispers
+   . https://www.google.com/search?q=tiny+lcd&tbm=isch
+   . http://adventofcode.com/2016
+   . http://adventofcode.com/2016/day/8/input